Steam-boiler control.



J. WILKINSON,

STEAM BOILER CONTROL.

APPLICATION TILED OGT.5, 1912.

Patented Apr. 28, 1914.

2 SHEETS-SHEET 1.

Inventor James WiIKinson H is 'cffttorne 8 "153;; Wltn TM/e wt, or

James WllKinson J. WILKINSON.

STEAM BOILER CONTROL.

APPLICATION FILED OCT. 5. 1912.

1,095,133, Patented Apr. 28, 1914.

2' SHEETS-SHEET 2 His QTLLorneH tions UNITED STATES PATENT OFFICE.

JAMES WILKINSON, OF BOSTON, MASSACHUSETTS, ASSIGNOR TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YOBI L smut-nouns common To all whom it may concern:

Be it known that I, JAMES WILKINSON, a citizen of the United States, residin at Boston, county of Suffolk, State of assachusetts, have invented certain new and useful Improvements in Steam-Boiler Control, of which the following is a specification.

This invention relates to apparatus for regulating the water and fuel supply of a steam boiler in accordance with the load upon it. To regulate a boiler to do certain shares of work, the supply of water and heat delivered to the boiler must be governed in accordance with the Volume of steam abstracted from said boiler. The steam pressure, the engine speed, the boiler water level, the quality of flue gas or steam, are mere incidentals. Control of the steam volume is the essential thing, and consequently'the effect of the governing apparatus which forms the subject matter of the present invention is to adjust the supply of water and heat applied to the boiler in accordance with the rate of flow of the steam takenfrom it.

The invention is of especial value where several boilers are connected to ether in a battery where it is essential to e ciency that each boiler supply its share of the total steam output. In such a plant, the regulators must act immediately to meet variaig demand, in order to preventan unequal stribution of the load.

In my improved regulator as herein shown, a pressure difference devlce 1n the steam main causes a fluctuation of a lever in acordance with variations in the flow of steam throu h said main, and this controls the admission of steam to a motor which opcrates devices for supplying fuel and air to the furnace. The feed water valve is controlled not only by the water level in the boiler but also by the rate of steam consumption by the motor, so that the supply of feed water is increased at the same time with the increase in fuel and to meet the increased demand for steam as indicated by an increased flow of steam in the main.

In the accompanying drawings, Figure 1 is a diagrammatic elevation of my improved boiler regulator; Fig. 2 is a sectional view of the motor governor. Fig.3 is a section of the pressure-responsive device gov- Specification of Letters Patent. Application filed October 5,1912. Serial No. 724,016.

Patented Apr. 28, 1914.

erning the feed Water supply, and Fig. 4 1s a section of the pressure nozzle plug.

The boiler 1 has a furnace provided with an air draft fan 2 and stoker 3, geared togetherby the shaft 4, and both driven by a motor such as the steam turbine 5. Steam is supplied to. the turbine through a pipe 6, which is controlled by a throttle valve 7. Fig. 2 showsthis throttle valve as of the sliding gate type, in which provision is made for increasing increments of steam with equal increments of opening. The stem 8 of the throttle valve is pivoted to the lever 9 of the governor. Said lever has a fixed fulcrum 10 andat a point between said fulcrum and the stem 8 two movable abutments engage opposite sides of said lever. These abutments are preferably flexible diaphragms 11, 12, each formlng one side of a pressure chamber 13, 14. Said chambers are respectively connected by pipes 15, 16 with the leading and trailing faces-of a pressure nozzle plu 17 inserted in the steam main 18 rying a ballfloat 27 heavier than said valve.

The lever is fulcrumed by a ball-joint to a rod 28 depending from a piston-29 working between stops 30 in a cylinder 31-10- cated in the steam space of the boiler. A spring 32 abuts between said piston and a follower 33, the latter being adjustable by means of a screw 34tapped through the head of the cylinder. The piston contains one or more constricted passages 35, through which steam can make its way to the pipe 6, which communicates with the upper end of the cylinder 3 The operation is as follows: If the demand I upon the boiler increases the flow of steam through the main 18, the increased velocity raises the pressure in the chamber 13 of diaphragm 11 to depress the lever 9. The wider opening of the throttle valve 7 thus produced admits more steam to the turbine .the governor, and thus acts through the 5, which speeds up and drives'the air fan 2 and the stoker 3 more rapidly. The result of the increased flow of steam is therefore an increased supply of fuel and air to generate steam faster. At the same time, the increased flow of steam to'the turbine through the pipe 6 causes the piston 29 to rise in the cylinder 31 because the retarding effect of the constricted passage 35 produces an unbalanced pressure below said piston. The lift of the rod 28 on the lever 26 causes it to fulcrum at the float 27, and open the valve 25w admit an increased supply of water to make up for the more rapid evaporation effected by the larger input of heat. Any lowering of the level of the water will also open the valve by the dropping of the float, the lever 26 fulcruming in that case on the end of the rod 28. I

The regulator above described is very sensitive in its action, any variation in the volume (and consequent velocity) of the steam passing through the main being immediately productive ;of a change in the heat and water input of the boiler to correspond with the changed demand; The action is quite independent of the pressure and temperature of the steam, condition of the fire and many other incidental factors, but is governed wholly by the quantity of steam drawn from the boiler. The regulator therefore tends to maintain a fairly uniform pressure of steam during ranges of flow from no load to full load;

In accordance with the provisions. of the patent statutes, I have described the principle of operation of my invention, together with the apparatus which I now consider to represent the best embodiment thereof; but

I desire to have it understood thatthe apparatus shown is only illustrative, and that the invention can be carried out by other means.

What I claim as new and desireto secure by Letters Patent of the United States, is 1. A steam boiler regulator comprising a device responsive to changes in the volume of steam drawn from said boiler, means admitting liquid to' the boiler, means supplying fuel to heat the boiler, and means dependent on said device for controllin the action of said liquid and fuel supp ying means.

2. A steam boiler regulator comprising a pressure difference device in the steam main, means for controlling the supply of fuel to the furnace of said boiler, means for controlling the supply of water for said boiler, and means controlled by said pressure difference device for governingthe operation of said fuel and water supplying means.

3. A steam boiler regulator comprising a nozzle plug in the steam main, a movable abutment connected with safithplug, a motor governed by said abutment, and air and fuel supplying mechanism driven by said motor.

4. A steam boiler regulator comprising. a nozzle plug in the steam main, a movable abutment connected to said plug, a motor governed by said abutment and taking steam from said boiler, air and fuel supplying mechanism driven by said'motor, and means responsive to the flow of steam to said motor for regulating the feed water.

5. A steam boiler regulator comprisin a nozzle plug in the steam main, a mova le abutment connected to said plug, a motor governed by said abutment and taking steam from said boiler, air and fuel supplying mechanism driven by said motor, a piston having a constricted passage through which steam must flow to said motor, and a feed water valve operated by said piston.

6. A steam boiler'regulator comprisin nozzle plug in the steam main, a mova b abutment connected to said plug, a motor governed by said abutment and taking steam from .said boiler, air and fuel supplying mechanism drivenby said motor, a piston having a constricted passage through. which steam must flow to said motor, a lever pivotally connected to said piston, a float at one end of said lever, and a feed water valve connected to the other end thereof.

In witness whereof, I have hereunto setmy hand this 2nd day of October, 1912.

JAMES WILKINSON.

Witnesses:

BENJAMIN B. HULL, GEORGE Wmsnmr. 

